Guidance paper claims cardiometabolic benefits of brewed tea

09 Dec 2022 --- Drinking a minimum of two cups of green or black tea a day is recommended as the new standard for reaping all of the nutritional benefits from the tasty, warm and traditional beverage according to experts at the Institute for the Advancement of Food and Nutrition Science, the organization that published the guidance.

Data shows that when flavan-3-oils are consumed in quantities of around 400-600 mg daily, which translates to about two cups of brewed tea, it can improve blood pressure, cholesterol and blood sugar levels.

“We know flavan-3-ols found in plant foods can impact cardiometabolic health, making our intake recommendations key to preventing, and improving, disease,” says Kristi Crowe-White, lead researcher on the guidance paper and research director at Advances in Nutrition.

The new guidelines could impact broader dietary recommendations and significantly improve the health of US citizens, according to Crowe-White.

“Magic” in the green and black varietals
Flavan-3-ols are plant compounds in many foods and drinks, such as tea, berries, craisins, apples and dark chocolate. “True teas” – such as black and green – were found to have the highest flavan-3-ols of all foods and beverages evaluated.

The guidelines extrapolated data from published research to form dietary recommendations for flavan-3-ol intake. Data were evaluated from 157 randomized control trials and 15 cohort studies as part of a recently published systematic review and meta-analysis to establish these guidelines.

Research has consistently demonstrated flavan-3-ols’ ability to help reduce the risk of diet-related conditions such as heart disease, stroke, and type 2 diabetes by helping to improve blood pressure, blood flow, cholesterol levels and blood sugar. Flavan-3-ols have even been shown to help protect the body’s cells from damage as we age.

Two cups support good cardio health The researchers found that black and green teas have the highest concentrations of flavan-3-ols of all foods and beverages evaluated.
The guidance indicates moderate evidence supporting cardiometabolic protection from consuming 400-600 mg of flavan-3-ols daily. In addition, a US National Cancer Institute study states that people who drink two cups of black tea a day have a 9-13% lower risk of early death than non-tea consumers.

Following these guidelines, research suggests health benefits can be seen from consuming about two eight-ounce cups of green or black tea each day. The guidelines are food-based recommendations, meaning the flavan-3-ols should be consumed through foods and drinks rather than through dietary supplements.

“With this guidance, we now have actionable recommendations about how much tea should be consumed to see health benefits,” says Peter Goggi, president of the Tea Association of the USA. 

Usuals suspects, diabetes and heart disease
According to the guidelines, heart disease is the leading cause of death in the US, costing the country US$229 billion annually.

In addition, more than 37 million US citizens (about 1 in 10) have diabetes, and a further 96 million (more than 1 in 3) have prediabetes. Diabetes is the seventh leading cause of death in the US, and annual medical costs and lost work and wages total an estimated US$327 billion.

Research conducted by the Wuhan University of Science and Technology, Wuhan, China, indicated that daily tea consumption reduces the risk of developing Type 2 diabetes. Every cup of green, black or oolong tea reduces the risk of Type 2 diabetes by about 1%.

The current research and guidance are the culmination of a collaboration between the Institute for the Advancement of Food and Nutrition Science, an international expert panel and The Academy of Nutrition and Dietetics to release recommendations for the daily consumption of specific quantities of flavan-3-ols.

Edited by Inga de Jong